Valvola 12SN7 Zoccolo Octal (Int.Octal, IO) K8A, USA 1935 (Codex=Vk) Utilizzata per Radio/TV-reception etc. Filamento Vf 12.6 Volt / If 0.3 Ampere / Indirect / Specified current AC/DC ~ = (Series working) Descrizione According to the nomenclature, an octal tube without a suffix as -G, -GT, etc. would presume a metal version of this tube, which does not exist. See under 12SN7GT.Foto originali